کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2447018 1553952 2015 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Genome-wide linkage disequilibrium in a Thai multibreed dairy cattle population
ترجمه فارسی عنوان
عدم همبستگی پیوندی ژنوم در یک جمعیت گاو شیری چند نژاد تایلندی
کلمات کلیدی
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم دامی و جانورشناسی
چکیده انگلیسی


• Mean of MAF across autosomes in multibreed was higher than purebred populations.
• LD from indicine and taurine may not be applicable to multibreed dairy populations.
• MAF distribution depended on Bos taurus or Bos indicus fractions in the population.
• The minimal sample sizes for accurate measures of LD were reported for D′ and r2.
• The results will be useful for GWAS and dairy genomic selection in the tropics.

The level of linkage disequilibrium (LD) plays an important role in increasing the power to detect associations for mapping quantitative trait loci in the genome and in increasing the accuracy of prediction of genomic estimated breeding values (GEBV). Thus, the objectives of this study were to evaluate the extent of LD in Thai multibreed dairy cattle and to determine factors that influence the estimation of LD. A total of 1413 multibreed dairy cows were genotyped for 8220 SNPs, covering 2507.24 Mb of the genome. The mean of minor allele frequencies (MAF) across autosomes was 0.37. All possible SNP pairs on the same chromosome were used to estimate LD across the 29 autosomes. High levels of LD were found in autosomes, particularly between SNP pairs at distances shorter than 50 kb. The mean of D′ (linkage disequilibrium relative to its maximum) and r2 (coefficient of correlation squared) for SNPs at 40–50 kb apart were 0.694 and 0.202, respectively. Overestimation of D′ occurred when the MAF threshold was low (0.05). The r2 was high when the MAF threshold was higher than 0.20, especially when the distance between markers was shorter than 50 kb. The minimum sample sizes required to obtain accurate measures of LD were 177 for D′ and 89 for r2. Results from this research will be useful for genome-wide association studies and genomic selection of dairy cattle in tropical regions.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Livestock Science - Volume 180, October 2015, Pages 27–33
نویسندگان
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